I've heard mixed things about it, it seems like it's a bit overhyped by people like Rogan. It seems like the evidence for treating asymptomatic people/people with no deficiency with Vit D supplementation is pretty inconclusive and not very strong at the time, more research is needed:
https://www.acpjournals.org/doi/10.7326/M14-2450
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD007470.pub3/full?highlightAbstract=mortality|withdrawn|vitamin|mortal
I think the main risk is your supplement being contaminated, assuming you're not overdosing downing 10,000 IU a day or something. So, I'd make sure you're getting a reputable brand that''s cGMP certified. If you have no deficiency symptoms then it's unknown whether it will make any difference and it might be unnecessary, but normal amounts probably do no harm also.
If you really want to look into it, maybe do a blood test and check your levels. If the levels are OK, it's inconclusive whether there's much benefit in taking it, from what I've seen.